Continuous metal melting



Oct. 28, 1958 o ss CONTINUOUS METAL MELTING Filed Jan. 27, 1956 INVENTOR. FREDERIC o. HEss 'fi wlw E www wg@ ATTORNEY.

United 2357542 atente& Oct. 28, 1958 CON TINUOUS METAL MELTING Frederic O. Hess, Philadelphia, Pa., assignor to Selas Corporation of America, Dresher, Pa., a corporatior of Pennsylvania Application January 27, 1956, Serial No. 561,725 2 claims. (CI. 22 209 The present invention relates to the melting of metal, and more particularly to a method of melting metal continuously for casting or other purposes.

It is commonly accepted practice at the present time t-o melt metals in batches, or to deposit unmelted metal in a bath of molten metal that is periodically used. Both of these methods require that a large body of metal be melted at one time and then held in a furnace or crucible until it is used. When the basic metal is to be alloyed with other ingredients, the batch method is almost universally used. Methods which require the holding of large bodies of metal in a liquid state are expensive both as to the equipment required as well as to the cost of fuel.

It is an object of the present invention to provide a method of melting and alloying metal which requires only a small body of molten metal to be maintained at any one time. It is a further object of the invention to provide a method of continuously melting metal and delivering this metal to alternate collection points where it can be alloyed and/ or used. It is also an object of the invention to provide a method of supplying molten metal continuously to a point of use, and to hold the metal at such a point for a suflicient length of time for alloying to take place.

-In following the present invention metal is continuously melted in a suitable furnace and is delivered as it is melted to a small pot to which the alloying elements may be added. As one pot is being filled and alloyed, another pot, the metal in which has been treated, is being used. By the time this pot is empty the metal in the first mentioned pot is ready for use. Thus while the metal is being melted continuously it is only required that a small amount of metal be held in the liquid state at any one time. A suflicient quantity of properly alloyed metal is always available for use.

The various features of novelty which characterize my invention are pointed out with particularity in the claims annexed to and forming a part of this specification. For a better Understanding of the invention, however, ts advantages and specific objects attained with its use, reference should be had to the accompanying drawings and descriptive matter in which I have illustrated and described a preferredembodiment of the invention.

In the drawings:

Fig. 1 is a section through one form of apparatus with which the method can be carried out,

Fig. 2 is a section taken on line 2-2 on Fig. 1, and

Fig. 3 is a section taken on line 3 3 of Fig. 1.

Referring to Fig. 1 there is shown -a furnace 1 which may be built in accordance with usual furnace construction practice. There is provided a furnace chamber, in which melting takes place, that is lined with refractory material 2. This material is backed up in the usual fashion by sheet metal work 3. The entire furnace is elevated above floor level upon suitable supporting structure 4.

The furnace hearth in this case is at a slight angle to the horizontal and is formed of a plurality of hearth tiles I 5 that are made of a refractory which will withstad the temperatures required and which is abrasive resistant. As shown in Fig. 2 the hearth tile is provided with curbs 6 on each side thereof so that the sloping hearth in fact forms a channel down which the metal can be moved and from which the molten metal continuously flows. At the left end of the furnace the hearth tile is extended as at 7 to form a platform upon which ingots to be melted are placed prior to the time that they are moved through the door 8 into the furnace chamber. This extension is suitably supported from the frame 4 by means of a bracket 9. The furnace chamber is heated by means of any suitable burners. Preferably, however, and as herein disclosed, the burners 11 are of the type shown inHess Patent 2,215,079. These burners are supplied with a combustible mixture of gas and air which is burned ir a refractory cup, -thereby heating this cup to incandescence. The radiant heat from the cup, in addition to the hot products of combustion, provides -an intense and uniform heat which is directed toward the metal passing down the hearth to melt the same.

As mentioned above, the hearth slopes slightly from its upper end at the entrance of the furnace to its lower end which is at the right in Fig. 1. This end is provided in each corner thereof, as best shown in Fig. 3, with spouts `12 and 13, respectively through one of which the molten metal drains continuously as it is being melted. The flow of metal through these spouts is controlled individually by a pair of gates 15 and 16 respectively that are received in suitable grooves in a high portion 14 of the curb 6 on each side of the spouts, and which can be raised and lowered to close ofi" the flow of metal. The gates are provided with control handles 17 and 18 respectively that extend through the top of the furnace where they may be grasped to move them in a vertical direction. It is apparent that these handles, as Well as the gates, must be provided with suitable guiding means so that they can accurately be moved in the respective spouts in order to cut off the flow of molten metal. Such guide means however, has not been shown.

As the metal leaves the spouts 12 and 13 it flows to one or another of a pair of collection points which are shown herein as taking the form of pots 19 that receive the molten metal. Each pot is provided with a flange 21 that rests upon the upper edge of a holding furnace 22. This furnace is constructed in accordance with ordinary furnace practice and is enough larger than the pots so that a combustion space extends between the pots and the furnace wall which has in it a plurality of burners indicated by 23. These burners are also preferably of the type disclosed in Patent 2,215,079 mentioned above. The bottom of the pots preferably rest upon pedestals 24 so that the entire weight thereof is not supported by the flanges 21 alone.

In the operation of the furnace metal in suitable form, such as ingots 25, is loaded on the extension 7 of the hearth and is moved by some suitable means toward the right into the'furnace chamber. As the metal moves toward the right, it is gradually melted and by the time it has reached the right end of the hearth the metal will be completely melted. The melting follows generally the line 26 which indicates a diminished size of the ingot as it moves through the furnace. It is intended that a continuous stream of ingots be supplied through the entrance 8 and that they be moved at such a rate that they are, completely melted by the time they reach the right end of the hearth. In this fashion there is a continual supply of metal to be melted and a continual supply of molten metal which is being drained at all times into one or the other of the holding pots through spouts 12 or 13.

The gate 15 will be' maintained in its upper position the furnace the pots-19Will be alternately filled from` spouts 12' and 13.

When one of the pots `19'has been filledgorwhile it is being filled, any desirable alloy metal, either in solid or molten state can be added to the pot. Thus the metal is given time to mix thoroughly with the alloy and age while the pot is being filled. Alternatively, the .alloying metal may alsos be melted in the furnace along with ingots 25 f by supplying suitable propo'tions thereof along with the ingots. Furthermore, one alloy can be added at one collection point and another alloy at the other collection point, thereby providing a plurality of alloys from a single melting furnace. During the time that one pot is being filled, metal from the other pot is being used for casting or other purposes. Thus, while one pot is being used the other one is being filled so that there is always a supply of metal at the proper temperature available. It will be obvious that more than two spouts and holding pots can be supplied from single furnace if it is so desired. The number of pots and spouts would depend somewhat upon the melting rate of the metal, the manner-of alloying, and upon the rate of use thereof.

From the above it will be seen that the method hei-ein contemplated provides a continuous supply of metal that is drained from a sloping dry hearth to one or the other of a plurality of collection points. At these points the metal can be alloyed if this is desirable, and the metal is used alternately; one collection pointybeing used to supply i metal for casting While the other is being filled. There is always a supply of metal available for any operation for which the metal is being melted. Thefurnace and method are primarily intended to be used for handling non-ferrous metals, although they are obviously not limited to this use. The term metal as used in the claims is intended to be either ferrous or non-ferrous.

What is claimed is:

1. The method of melting and treatng metal which comprises moving a supply of solid metal to and through a melting zone, applying heat continuously to said metal as it is moving through said zone gradually to melt the same, completing the melting of the metal by the time it reaches the end of said zone, withdrawing metal continuously as it is being melted from the discharge end of said melting zone alternately at one or the other of a pair of discharge points, supplying the metal discharged from said points to receptacles in which it may be treated, and filling one receptacle and treatng the metal therein while metal in the other receptacle is being used.

2. The` method of melting and treatng metal which comprises moving metal into and through a substantially horizontal melting zone, applying heat to the metal the entire time it is in said zone, the rate of movement of the metal and application of heat being such that the solid metal introduced into said zone istgradually and completely melted by the time it reaches the discharge end thereof, continuously removing the melted metal from h the melting zone in sequence through one or another of a plurality of discharge spouts as it is melted and placing it in a receptacle associated with each spout, and treating the metal being received in a given receptacle while the metal already treated in another receptacle is being y used.

References Cited in the file of this patent UNITED STATES PATENTS 912,298 Evans Feb. 16, 1909 1,06l,280 Ford May 13, 1913, 1,089,377 Hibbard Ma`r. 3, 1914 1,092,938 Mellon Apr. 14, 1914 1,13l,799 Smith Mar. 16, 1915 1,347,741 Hadfield July 27, 1920 i 1,476,106` Rochlitz Dec. 4, 1923 1,965,928 McGregor July 10, 1934 2,15 7,55O Lindner May 9, 1939 2,302,999 O'Brien Nov. 24, 19442 2,458,236 Wolff Jan. 4, 1949 

